Western legal prehistory aims to reconstruct some of the earliest proto-legal and cultural developments that gave rise to Western legal systems and the rule of law. So construed, our understanding of Western legal prehistory is currently highly undeveloped. One reason for this fact is methodological: without the aid of written sources, reconstructions of human prehistory can prove difficult. Recent advances in a broad range of cognate fields have, however, accumulated past a critical tipping point, and we are now in a secure enough position to begin to reconstruct important aspects of Western legal prehistory.

This Article draws upon and develops these contemporary findings to reconstruct the most plausible genealogical shape of Western legal prehistory. In the process, it reaches a somewhat surprising conclusion. On the traditional view, the most important traditions relevant to the rise of Western law and Western Civilization are said to have originated in ancient Greece, Rome, and Israel. This traditional view is, however, based primarily on historical sources, and the reconstructions in this Article suggest that important precursors of these traditions very likely emerged much earlier and much further to the East. In fact, some of the most important traditions relevant to the emergence of large-scale civilizations with the rule of law in the West would appear to represent just one branch a much richer family of traditions, which began to emerge around 4500 BC in the Eastern-Iran-Bactria-Indus-Valley region. Beginning at this early time, this region began to produce one of the very first ancient civilizations to arise within our natural history as a species (viz., the “Harappan” or “Indus Valley” Civilization), and the people in this region must have therefore developed some of the very first cultural traditions that were specifically adapted to sustaining large-scale civilizations with incipient law. I will be arguing that these ancient developments most likely had a much closer and much more intimate relationship to some of the earliest precursors of Western tradition than has commonly been recognized because these precursors of Western tradition ultimately originated closer to ancient Bactria — which is an area directly adjacent to the Indus Valley but to the east of the Caspian Sea — during this very same time period. The reconstructions developed in this Article will thus allow me to decipher what I take to be the most plausible early genealogical shape of our legal family tree, and to suggest a number of important but underappreciated relationships that obtain between our modern Western traditions and a range of other Eurasian traditions with which the West has typically been contrasted.

In today’s world, it is, moreover, especially important that we try to reconstruct the genealogical structure of Western legal prehistory and obtain a better understanding of our deep past. There is now an accumulating body of empirical work, which suggests that we can explain a broad range of features of modern societies in terms of the origins of their laws. This literature suggests that legal origin variables can have strong effects on issues as diverse as corporate governance structure, labor regulations, the robustness of capital markets, and even literacy and infant mortality rates. Whether and how a modern society functions best would thus appear to depend at least in part on the origins of their legal traditions. At the same time, however, both the present legal origins literature and much comparative law scholarship distinguish primarily between the civil versus common law origins of a nation’s legal system, or between both of these types of Western law and various non-Western legal systems; and the findings of this literature have not yet been fully harmonized with the swath of known difficulties that many developing nations have faced in transitioning to large-scale societies with the rule of law regardless of their civil- or common-law origins. The family trees that are employed in the current literature are, moreover, typically identified from the historical record and therefore fail to detect any relevant relations that might have arisen in human prehistory. They tend to focus on a conception of law as a set of publicly stated rules and procedures that are largely exogenous to the underlying cultural traditions and psychological attitudes that tend to support flourishing legal systems. They therefore fail to detect the kinds of emergent cultural traditions (including the culturally emergent psychological attitudes) that first allowed humans to transition from hunter-gatherer forms of life into larger-scale civilizations with the rule of law.

The reconstruction offered here will, by contrast, allow us to see almost half of the large-scale mega empires that have arisen throughout world history — including all those that have arisen in the modern West — as having a shared cultural origin that goes much further back in time. The tradition in question first emerged with some of our very first human forays out of hunter-gatherer living and into settled agricultural living with large-scale civilizations and incipient legal traditions. An understanding of this deeper family tree should therefore have important empirical implications. This work can, for example, be used to help explain why certain exportations of Western-style legal institutions have worked so well while others have not. This work can also be used to identify a number of important but underappreciated features of Western traditions that are shared with these broader Eurasian traditions and have been playing a critical — if underappreciated — role in helping to sustain various forms of social complexity and economic development over the course of world history. Hence, this work can help us understand better some of the full causes and conditions of our modern success in the West. Inquiries of this kind should have special urgency today, given the massive exportations of Western law and Western legal institutions to so many other parts of the world and given the increased pressures toward Westernization that are being felt around the globe.